The present invention relates to a new and improved construction of piston pump installation for conveying sludge-type materials and granulated and solid materials with added fluid, composed of one or more, preferably two, cylinders arranged adjacent and parallel to one another with axially reciprocating pistons therein, a respective valve provided at the front end of each cylinder, and a drive and control device located at the rear, opposite end, and further relates to a method for operating the piston pump installation according to the invention.
For conveying waste materials, pre-treated sewage sludge or other pasty materials, such as, for example, in sewage treatment plants and in the paper and sugar industry, piston pumps have been increasingly used in recent times, in addition to the generally customary conveying devices, such as chain conveyors or conveyor belts, by means of which these materials are conveyed.
In the case of these known piston pumps, fluid is added to the material to be conveyed so that a sludge-type mass is formed. The piston generates a reduced pressure in the pump cylinder and, after opening a valve, the material is sucked into the cylinder. By moving the piston in the opposite direction, the material is pressed under high pressure through an ejector valve into the pipelines.
This known arrangement has the disadvantage that only intermittent charging is possible so that the pipelines are also exposed to a non-uniform pressure load or stress and leakages and defects can occur therein.